// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: http://codemirror.net/LICENSE

(function(mod) {
  if (typeof exports == 'object' && typeof module == 'object')
    // CommonJS
    mod(require('../../lib/codemirror'));
  else if (typeof define == 'function' && define.amd)
    // AMD
    define(['../../lib/codemirror'], mod);
  // Plain browser env
  else mod(CodeMirror);
})(function(CodeMirror) {
  'use strict';

  CodeMirror.defineMode('smalltalk', function(config) {
    var specialChars = /[+\-\/\\*~<>=@%|&?!.,:;^]/;
    var keywords = /true|false|nil|self|super|thisContext/;

    var Context = function(tokenizer, parent) {
      this.next = tokenizer;
      this.parent = parent;
    };

    var Token = function(name, context, eos) {
      this.name = name;
      this.context = context;
      this.eos = eos;
    };

    var State = function() {
      this.context = new Context(next, null);
      this.expectVariable = true;
      this.indentation = 0;
      this.userIndentationDelta = 0;
    };

    State.prototype.userIndent = function(indentation) {
      this.userIndentationDelta =
        indentation > 0
          ? indentation / config.indentUnit - this.indentation
          : 0;
    };

    var next = function(stream, context, state) {
      var token = new Token(null, context, false);
      var aChar = stream.next();

      if (aChar === '"') {
        token = nextComment(stream, new Context(nextComment, context));
      } else if (aChar === "'") {
        token = nextString(stream, new Context(nextString, context));
      } else if (aChar === '#') {
        if (stream.peek() === "'") {
          stream.next();
          token = nextSymbol(stream, new Context(nextSymbol, context));
        } else {
          if (stream.eatWhile(/[^\s.{}\[\]()]/)) token.name = 'string-2';
          else token.name = 'meta';
        }
      } else if (aChar === '$') {
        if (stream.next() === '<') {
          stream.eatWhile(/[^\s>]/);
          stream.next();
        }
        token.name = 'string-2';
      } else if (aChar === '|' && state.expectVariable) {
        token.context = new Context(nextTemporaries, context);
      } else if (/[\[\]{}()]/.test(aChar)) {
        token.name = 'bracket';
        token.eos = /[\[{(]/.test(aChar);

        if (aChar === '[') {
          state.indentation++;
        } else if (aChar === ']') {
          state.indentation = Math.max(0, state.indentation - 1);
        }
      } else if (specialChars.test(aChar)) {
        stream.eatWhile(specialChars);
        token.name = 'operator';
        token.eos = aChar !== ';'; // ; cascaded message expression
      } else if (/\d/.test(aChar)) {
        stream.eatWhile(/[\w\d]/);
        token.name = 'number';
      } else if (/[\w_]/.test(aChar)) {
        stream.eatWhile(/[\w\d_]/);
        token.name = state.expectVariable
          ? keywords.test(stream.current())
            ? 'keyword'
            : 'variable'
          : null;
      } else {
        token.eos = state.expectVariable;
      }

      return token;
    };

    var nextComment = function(stream, context) {
      stream.eatWhile(/[^"]/);
      return new Token(
        'comment',
        stream.eat('"') ? context.parent : context,
        true,
      );
    };

    var nextString = function(stream, context) {
      stream.eatWhile(/[^']/);
      return new Token(
        'string',
        stream.eat("'") ? context.parent : context,
        false,
      );
    };

    var nextSymbol = function(stream, context) {
      stream.eatWhile(/[^']/);
      return new Token(
        'string-2',
        stream.eat("'") ? context.parent : context,
        false,
      );
    };

    var nextTemporaries = function(stream, context) {
      var token = new Token(null, context, false);
      var aChar = stream.next();

      if (aChar === '|') {
        token.context = context.parent;
        token.eos = true;
      } else {
        stream.eatWhile(/[^|]/);
        token.name = 'variable';
      }

      return token;
    };

    return {
      startState: function() {
        return new State();
      },

      token: function(stream, state) {
        state.userIndent(stream.indentation());

        if (stream.eatSpace()) {
          return null;
        }

        var token = state.context.next(stream, state.context, state);
        state.context = token.context;
        state.expectVariable = token.eos;

        return token.name;
      },

      blankLine: function(state) {
        state.userIndent(0);
      },

      indent: function(state, textAfter) {
        var i =
          state.context.next === next &&
          textAfter &&
          textAfter.charAt(0) === ']'
            ? -1
            : state.userIndentationDelta;
        return (state.indentation + i) * config.indentUnit;
      },

      electricChars: ']',
    };
  });

  CodeMirror.defineMIME('text/x-stsrc', { name: 'smalltalk' });
});
